1. Field of the Invention
The present invention relates to an information processing apparatus, control method therefor, and program.
2. Description of the Related Art
Conventionally, some image processing apparatuses, which are examples of information processing apparatuses, limit functions available to a user based on results of user authentication. Such image processing apparatuses have user IDs of authorized users registered in advance, for example, to limit users. When an image processing apparatus receives a user ID input by a user, the image processing apparatus permits the user to log in to the image processing apparatus only if the received user ID matches a pre-registered user ID. Once login is permitted, the image processing apparatus retains settings received from the user and continues to display a setting screen based on the retained settings until the user logs out. When the user logs out of the image processing apparatus, the image processing apparatus discards the retained settings. Subsequently, when the user logs in again, the image processing apparatus displays an initial screen. Regarding a logout method, the user is logged out of the image processing apparatus, for example, when there is a logout request from the user or when there is no response from the user for a predetermined time.
However, with the logout method described above, if the user forgets to issue a logout request or within a predetermined time before the user is logged out, other users who are not authorized can use the image processing apparatus. This degrades security. To deal with this problem, a technique is known which detects the presence of a user in front of the apparatus using an infrared sensor (Japanese Patent Laid-Open No. 10-207584). The technique detects the presence of a user in front of the apparatus using a body sensor, and when the human presence ceases to be detected, puts the apparatus into a power-saving mode called OFF mode or Suspend mode.
However, the conventional technique described above has a problem as follows. For example, if the user moves out of the body sensor's range once and returns soon, the user has to make settings anew. In this way, although the conventional method prevents security degradation, it decreases user convenience.